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Relative Reduction (relative + reduction)
Selected AbstractsShb null allele is inherited with a transmission ratio distortion and causes reduced viability in uteroDEVELOPMENTAL DYNAMICS, Issue 9 2007Vitezslav Kriz Abstract SHB is an Src homology 2 domain-containing adapter protein that has been found to be involved in numerous cellular responses. We have generated an Shb knockout mouse. No Shb,/, pups or embryos were obtained on the C57Bl6 background, indicating an early defect as a consequence of Shb - gene inactivation on this genetic background. Breeding heterozygotes for Shb gene inactivation (Shb+/,) on a mixed genetic background (FVB/C57Bl6/129Sv) reveals a distorted transmission ratio of the null allele with reduced numbers of Shb+/+ and Shb,/, animals, but increased number of Shb+/, animals. The Shb, allele is associated with various forms of malformations, explaining the relative reduction in the number of Shb,/, offspring. Shb,/, animals that were born were viable, fertile, and showed no obvious defects. However, Shb+/, female mice ovulated preferentially Shb, oocytes explaining the reduced frequency of Shb+/+ mice. Our study suggests a role of SHB during reproduction and development. Developmental Dynamics 236:2485,2492, 2007. © 2007 Wiley-Liss, Inc. [source] Genetic Allee effects on performance, plasticity and developmental stability in a clonal plantECOLOGY LETTERS, Issue 6 2000M. Fischer Negative effects of small population size on fitness, so-called Allee effects, may threaten population persistence even in intact habitat remnants. We studied genotypes of 14 isolated populations of the clonal plant Ranunculus reptans, for which molecular genetic (RAPD-) variability is higher for large than for small populations. In a competition-free greenhouse environment vegetative offspring of genotypes from large populations produced more rosettes and flowers, indicating higher fitness. Within-genotype coefficients of variation in performance traits, indicating developmental instability, were lower for genotypes from populations with higher RAPD-variability. In competition with a taller grass, we found relative reduction in leaf length less pronounced for plants from large populations, suggesting higher adaptive plasticity. Our experimental study of a plant with predominantly vegetative reproduction suggests, that negative genetic effects of recent habitat fragmentation, which so far rather were expected in plants with frequent sexual reproduction, are more severe and more common than previously acknowledged. [source] Chronic nicotine treatment changes the axonal distribution of 68 kDa neurofilaments in the rat ventral tegmental areaEUROPEAN JOURNAL OF NEUROSCIENCE, Issue 5 2002Andrea Sbarbati Abstract Region-specific decreases of neurofilament proteins (NF) were described in the ventral tegmental area (VTA) of rats treated chronically with morphine, cocaine or alcohol. In a previous study, we demonstrated that NF levels were also changed in the VTA after chronic treatment with nicotine. The aim of this study was to clarify the submicroscopic basis of decreased immunoreactivity for NF-68, NF-160 and NF-200, as determined by using NR4, BF10 and RT97 antibodies, respectively. Microdensitometric analysis of brain sections showed that immunoreactivity for all NF was reduced in the VTA of animals exposed chronically to nicotine (0.4 mg/kg per day, 6 days of treatment), when compared to rats exposed to saline. Reduction in immunoreactivity was significant for NF-68 (P < 0.05), NF-160 (P < 0.01) and NF-200 (P < 0.05), showing a relative reduction of 34%, 42% and 38%, respectively, when compared to saline-treated rats. No difference was observed for any of the NF under study when immunoreactivity measurements in the substantia nigra were compared. Ultrastructural analysis was applied to evaluate changes in NF-68, NF-160 and NF-200 immunoreactivity in regions of the VTA that contain dopaminergic neurons following chronic nicotine treatment. At the electron microscopic level, no degenerative changes were found in neurons or glial cells of the VTA. With ultrastructural immunohistochemistry, evaluation of the homogeneity parameter of NF distribution showed a loss of homogeneity for NF-68 linked to the nicotine treatment. In areas in which NF organization appeared well preserved, analysis of the numerical density of NF revealed no significant difference for NF-68 (897/µm2 vs. 990/µm2), NF-160 (970/µm2 vs. 820/µm2) and NF-200 (1107/µm2 vs. 905/µm2) in nicotine-treated rats when compared to saline-treated rats. These results confirm that nicotine shares the same properties with cocaine and morphine in reducing NF in the VTA, a key brain structure of the rewards system, and that chronic nicotine treatment changes the axonal distribution of 68 kDa neurofilaments in the rat VTA. [source] Adjuvant chemotherapy in colon cancer: what is the evidence?INTERNAL MEDICINE JOURNAL, Issue 3 2003A. Haydon Abstract Over the last 12 years, numerous randomized trials have addressed the role of adjuvant chemotherapy in resected colon cancer. Together, these studies give conclusive evidence of the benefit of adjuvant 5-fluorouracil combined with folinic acid in stage III (node positive) disease and this is now considered the standard of care. The chemotherapy appears to be equally effective whether it is given daily for 5 days per month or on a weekly schedule. The overall effect is a relative reduction in tumour recurrence of 25% or an absolute improvement in survival of 10%. However, doubt remains as to the role of adjuvant chemotherapy in stage II colon cancer. To date, most of the randomized trials have demonstrated a relative reduction in tumour recurrence but have not shown any significant impact on survival. It seems likely that this inability to demonstrate a survival benefit from adjuvant chemotherapy in stage II disease relates to the fact that the trials have been underpowered to do so. Nevertheless, the absolute survival advantage is only about 2% and clinicians need to weigh this against the costs and toxicities of the treatment when managing these patients. (Intern Med J 2003; 33: 119,124) [source] Evaluation of the nano-oligosaccharide factor lipido-colloid matrix in the local management of venous leg ulcers: results of a randomised, controlled trialINTERNATIONAL WOUND JOURNAL, Issue 2 2008Jean-Luc Schmutz Abstract The nano-oligosaccharide factor (NOSF) is a new compound aiming to promote wound closure mainly through inhibition of matrix metalloproteinase (MMP) activity. This factor is incorporated within a lipido-colloid matrix (Techonology Lipido-Colloid-NOSF matrix) and locally released in the wound. The objective of this study was to document the performance (non inferiority or superiority) of the NOSF relative to the Promogran® matrix (oxidised regenerated cellulose, ORC) effect in the local management of venous leg ulcers (VLUs). This was a 12-week, open, two-arm, multicentre, randomised study. Patients were selected if the area of their VLU [ankle brachial pressure index ,0·80] ranged from 5 to 25 cm2 with a duration ,3 months. Ulcers had to be free from necrotic tissue. In addition to receiving compression bandage therapy, patients were randomly allocated to either NOSF matrix or ORC treatment for 12 weeks. The VLUs were assessed on a weekly basis and wound tracings were recorded. Percentage wound relative reduction (%RR) was the primary efficacy criterion. Secondary objectives were wound absolute reduction (AR), healing rate (HR) and % of wounds with ,40% reduction compared with baseline. A total of 117 patients were included (57 NOSF matrix and 60 ORC). Mean population age was 71·3 ± 13·5 years, body mass index was ,30 kg/m2 in 39·3% and 15·4% were diabetics. Fifty-six per cent of the VLUs were present for >6 months, 61% were recurrent and 68% were stagnating despite appropriate care. Mean wound area at baseline was 11·2 ± 7·4 cm2. At the last evaluation, mean difference between the groups for %RR was 33·6 ± 15·0% in favour of NOSF matrix with a unilateral 95% confidence interval (CI) lower limit of 8·6% not including the null value. Therefore, a superiority of NOSF matrix effect compared with ORC was concluded (P = 0·0059 for superiority test). The median of the wound area reduction was 61·1% and 7·7% in the NOSF matrix and control groups, respectively (per-protocol analysis), or 54·4% versus 12·9% in intent-to-treat analysis (p = 0·0286). Median AR was 4·2 cm2 in the NOSF group and 1·0 cm2 with ORC (P = 0·01). Median HR was ,0·056 and ,0·015 cm2/day in NOSF and ORC groups, respectively (P = 0·029). By logistic regression, the NOSF versus control odds ratio to reach 40% area reduction was 2·4 (95% CI: 1·1,5·3; P = 0·026). In the oldest and largest VLUs, a strong promotion of healing effect was particularly observed in the NOSF matrix group compared with the control group. NOSF matrix is a very promising option for the local management of chronic wounds, especially for VLUs with poor healing prognosis. [source] Effect of P6 acustimulation on post-operative nausea and vomiting in patients undergoing a laparoscopic cholecystectomyACTA ANAESTHESIOLOGICA SCANDINAVICA, Issue 10 2009U. H. FREY Background Non-pharmacologic techniques such as electrical acustimulation may mitigate post-operative nausea and vomiting (PONV). The primary purpose of this study was to investigate the effectiveness of acustimulation on attenuating PONV. Moreover, we tested whether a pre- or a post-induction application of acustimulation results in differences in PONV reduction. Methods In this prospective, double-blind, randomized, controlled trial, we studied 200 patients undergoing a laparoscopic cholecystectomy during propofol (induction) fentanyl/isoflurane/atracurium (maintenance) anaesthesia. In the acustimulation group (n=101), subdivided into groups with pre-induction (n=57) and post-induction (n=44) acustimulation, an active ReliefBand® device was placed at the P6 acupoint. In the sham group (n=99), also subdivided into pre-induction (n=55) or post-induction (n=44) groups, an inactive device was applied instead. The ReliefBand® remained in place for 24 h after surgery. Nausea and vomiting/retching were recorded at 2, 6, and 24 h post-operatively. Results The incidence of early nausea (up to 2 h) was significantly lower in the acustimulation than in the sham group (29% vs. 42%; P=0.043). No significant effect could be detected for retching/vomiting. Moreover, acustimulation showed no effect on PONV after 6 and 24 h. Risk factor analysis (female gender, non-smoker, history of PONV/motion sickness, and post-operative morphine usage) revealed a relative reduction in risk of 40% for nausea (P=0.021) and 55% for retching/vomiting (P=0.048) in patients with three or four risk factors present. The timing of (pre- vs. post-induction) acustimulation had no significant effect on PONV reduction. Conclusion Acustimulation at the P6 acupoint reduces early nausea, but not vomiting, after laparoscopic cholecystectomy, irrespective of its pre- or post-induction application. [source] The relationship of total and per-gram rankings in competitive effect to the natural abundance of herbaceous perennialsJOURNAL OF ECOLOGY, Issue 1 2001Timothy G. Howard Summary 1,Using a field experiment and a garden experiment, I estimated the rankings in total and per-gram competitive effect of non-woody perennial old-field species. 2,Total competitive effects were defined as the relative reduction in growth of a target from no-neighbour to with-neighbour conditions. Per-gram competitive effects were defined as the per-unit relative reduction in target growth among increasing neighbour densities, and were determined from the shape of a nonlinear curve fit through a distribution of normalized target performance against neighbour mass. 3,In both experiments, mean total competitive effect differed significantly among species, indicating a strong competitive hierarchy. In the garden experiment only species at opposite ends of the ranking differed significantly in per-gram competitive effect, resulting in a weaker competitive hierarchy based on this measure. 4,Nonetheless, rankings of per-gram competitive effect were more strongly correlated with rank in abundance than were rankings of total competitive effect. 5,Per-gram competitive effect may be more predictive of natural abundance than total competitive effect for at least two reasons. The effects of neighbour abundance on targets are nonlinear, and unlike total effects, per-gram estimates of competitive effect may therefore indicate how competition changes over time with changing neighbour densities. Also, if higher per-gram competitive effect reflects higher per-unit nutrient uptake rates, it would probably be advantageous to a species throughout the individual's life span, rather than only when the individual is larger than its surrounding neighbours. [source] Aflatoxin Inactivation Using Aqueous Extract of Ajowan (Trachyspermum ammi) SeedsJOURNAL OF FOOD SCIENCE, Issue 1 2005Shruti S. Hajare ABSTRACT: Aqueous extract of ajowan seeds was found to contain an aflatoxin inactivation factor (IF). Thin layer chromatography analysis of the toxins after treatment with IF showed relative reduction of aflatoxin G1 > G2 > B1 > B2. Quantification of toxin using a fluorotoxin meter as well as the Enzyme Linked Immuno s orb ent Assay (ELISA) confirmed these findings. An approximate 80% reduction in total aflatoxin content over the controls was observed. This observed phenomenon of reduction in total toxin was referred to as toxin inactivation. Temperature was found to influence the rate of toxin inactivation. At 45 °C, it was found to be rapid during the initial 5 h and slowed later. The IF was found to retain considerable activity even after boiling and autoclaving, indicating partial heat stability. The activity was lost below pH 4.0. Above pH 4.0, it increased gradually, reaching the maximum at pH 10.0. IF was found to be stable to gamma irradiation. Toxin decontamination in spiked corn samples could be achieved using IF. This study emphasizes the potential of ajowan IF in aflatoxin removal from contaminated food commodities. However, the biological toxicity, if any, of the IF inactivated aflatoxins needs to be confirmed, and the work in this direction is in progress. [source] Changing GPs' prescription patterns through guidelines and feedback.PHARMACOEPIDEMIOLOGY AND DRUG SAFETY, Issue 6 2007Intervention study Abstract Purpose To investigate whether and how a multi-dimensional intervention including clinical guidelines on the choice of medical treatment in the primary and the secondary health care sector, and individual feedback to general practices about their own and other practices' prescription patterns in five Anatomical Therapeutic Chemical classification system (ATC)-groups was followed by changes in the practices' prescription pattern. Methods Prospective historical registry study and a questionnaire study of GPs' self-reported use of guidelines and feedback. Results In every ATC-group the number of prescribed defined daily doses (DDDs) kept growing after the intervention, while potential savings by DDD decreased. Individual practices' changes in the prescription pattern differed by ATC-group and practices with high potential savings/DDD before the intervention showed the greatest relative reduction in potential savings/DDD. The county's average cost/DDD for the five ATC-groups declined from above the Danish average before the intervention to a level below the average cost/DDD after the intervention. In the questionnaire study (response rate: 79%), 69% of respondents had read the guidelines and 78% reported that the feedback influenced their prescription of drugs. Conclusions The observed changes in drug costs and potential savings were not due to volume effects but a combination of price effects, including generic substitution and choice of less expensive analogues, demonstrating that it is possible to change GPs' prescription patterns without interfering with patients' access to treatment or with GPs' clinical freedom.' Copyright © 2007 John Wiley & Sons, Ltd. [source] Gait dynamics of Cebus apella during quadrupedalism on different substratesAMERICAN JOURNAL OF PHYSICAL ANTHROPOLOGY, Issue 2 2010Kristian J. Carlson Abstract Primates are distinguished from many mammals by emphasizing arboreal lifestyles. Primate arboreal adaptations include specializations for enhancing balance and manipulative skills. Compliant gait and diagonal sequence (DS) footfalls are hypothesized mechanisms for improving balance during arboreal quadrupedalism (AQ), while simultaneously permitting vertical peak force reductions sustained by limbs, particularly forelimbs (FLs). Capuchin monkeys (Cebus apella) are arboreally-adapted quadrupeds that use both lateral sequence (LS) and DS footfalls. As tool-users, capuchins experience selective pressures for FL manipulative capabilities, which seemingly conflict with encountering substantial locomotor stresses. We evaluate kinetic and 3-D kinematic data from 172 limb contacts of two adult males on terrestrial and arboreal substrates to address questions about C. apella gait compliancy, kinematics of LS and DS footfalls during quadrupedalism on different substrates, and whether capuchins reduce FL vertical peak forces relative to hind limb (HL) forces more than other primates that use tools or those that do not. Lower vertical peak forces during AQ are consistent with compliant gait, but mixed kinematic results obscure how the reduction occurs. Forearm adduction angle is one consistent kinematic difference between terrestrial and arboreal quadrupedalism, which may implicate frontal plane movements in gait compliancy. Major differences between DS and LS gaits were not observed in kinetic or kinematic comparisons. Capuchins exhibit low FL/HL vertical peak force ratios like several anthropoids, including tool-users (e.g., chimpanzees), and species not considered tool-users in free-ranging conditions (e.g., spider monkeys). Additional selective pressures besides simply tool use appear responsible for the relative reduction in primate forelimb forces. Am J Phys Anthropol, 2010. © 2010 Wiley-Liss, Inc. [source] The influence of masticatory loading on craniofacial morphology: A test case across technological transitions in the Ohio valleyAMERICAN JOURNAL OF PHYSICAL ANTHROPOLOGY, Issue 2 2010Carolina Paschetta Abstract Masticatory loading is one of the main environmental stimuli that generate craniofacial variation among recent humans. Experimental studies on a wide variety of mammals, including those with retrognathic postcanine teeth, predict that responses to masticatory loading will be greater in the occlusal plane, the inferior rostrum, and regions associated with the attachments of the temporalis and masseter muscles. Here we test these experimentally-derived predictions on an extinct human population from the middle and upper Ohio valley that underwent a marked shift from hunting-gathering to extensive farming during the last 3,000 years and for which we have good archaeological evidence about diet and food processing technology. Geometric morphometric methods were used to detect and measure the putative effect of diet changes on cranial shape independent of size. Our results partially confirm only some of the experimental predictions. The effect of softer and/or less tough diets on craniofacial shape seem to be concentrated in the relative reduction of the temporal fossa and in a displacement of the attachment of the temporal muscle. However, there were few differences in craniofacial shape in regions closer to the occlusal plane. These results highlight the utility of exploring specific localized morphological shifts using a hierarchical model of craniofacial integration. Am J Phys Anthropol, 2010. © 2009 Wiley-Liss, Inc. [source] Clinical assessment of a new anaesthetic drug administration system: a prospective, controlled, longitudinal incident monitoring study,ANAESTHESIA, Issue 5 2010C. S. Webster Summary A safety-orientated system of delivering parenteral anaesthetic drugs was assessed in a prospective incident monitoring study at two hospitals. Anaesthetists completed an incident form for every anaesthetic, indicating if an incident occurred. Case mix data were collected and the number of drug administrations made during procedures estimated. From February 1998 at Hospital A and from June 1999 at Hospital B, until November 2003, 74 478 anaesthetics were included, for which 59 273 incident forms were returned (a 79.6% response rate). Fewer parenteral drug errors occurred with the new system than with conventional methods (58 errors in an estimated 183 852 drug administrations (0.032%, 95% CI 0.024,0.041%) vs 268 in 550 105 (0.049%, 95% CI 0.043,0.055%) respectively, p = 0.002), a relative reduction of 35% (difference 0.017%, 95% CI 0.006,0.028%). No major adverse outcomes from these errors were reported with the new system while 11 (0.002%) were reported with conventional methods (p = 0.055). We conclude that targeted system re-design can reduce medical error. [source] Reduced sexual maturation in male post-smolt 1+ Atlantic salmon (Salmo salar L.) by dietary tetradecylthioacetic acidAQUACULTURE RESEARCH, Issue 5 2009Henriette Alne Abstract In the present study, the possible effect of dietary treatment on early sexual maturation in post-smolt Atlantic salmon, without any negative effect regarding growth, was investigated. The experiment was performed using 4400 individually marked (Pit tag) 1+ salmon, fed either a control diet or a diet supplemented with 0.5% tetradecylthioacetic acid (TTA) in duplicates for 3, 6 or 12 weeks after sea transfer. Compared with the control, dietary supplementation of TTA resulted in a threefold reduction in incidence of sexual mature males (0.6% vs. 1.8%). A curve-linear relationship between relative reduction in maturation and weeks of feeding TTA was found, indicating that the effect is most marked as a result of the first weeks of feeding and then levelling off. No negative dietary impact on growth was observed. As the level of fat in the muscle was reduced by dietary TTA, it seems that post-smolt supplemented dietary TTA do not accumulate high enough energy stores to start the maturation process, whereas the energy-enhancing effect of TTA due to increased fatty acid oxidation capacity may maintain the growth potential. Compared with immature salmon, sexually maturing fish revealed increased spring growth before the onset of maturation. [source] Coral community decline at a remote Caribbean island: marine no-take reserves are not enoughAQUATIC CONSERVATION: MARINE AND FRESHWATER ECOSYSTEMS, Issue 7 2007Vânia R. Coelho Abstract 1.Coral reefs around the world have been deteriorating over decades owing to anthropogenic pressure. In the Caribbean recent rates of decline are alarming, particularly for coral reefs under high local human impact, many of which are severely degraded, although regions with lower direct anthropogenic influence seem less affected. 2.Little Cayman is a relatively undeveloped island, with less than 150 permanent residents. About 20% of its reefs have been protected by no-take marine reserves since the mid-1980s. We analysed the dynamics of coral communities around the island from 1999 to 2004 in order to test the hypothesis that a lack of major local anthropogenic disturbances is enough to prevent decline of coral populations. 3.Live hard coral coverage, coral diversity, abundance, mortality, size, and prevalence of disease and bleaching were measured using the Atlantic and Gulf Rapid Reef Assessment methodology (line transects) at nine sites. Despite the apparent undisturbed condition of the island, a 40% relative reduction of mean live coral coverage (from 26% to 16%, absolute change was 10%) was recorded in five years. Mean mortality varied from year to year from 23% to 27%. Overall mean diameter and height have decreased between 6% and 15% on average (from 47 to 40 cm for diameter, and from 31 to 29 cm for height). 4.The relative abundance of large reef builders of the genus Montastraea decreased, while that of smaller corals of the genera Agaricia and Porites increased. Disease prevalence has increased over time, and at least one relatively large bleaching event (affecting 10% of the corals) took place in 2003. 5.Mean live coral cover decline was similar inside (from 29% to 19%) and outside (from 24% to 14%) marine no-take reserves. No significant difference in disease prevalence or clear pattern in bleaching frequency was observed between protected and non-protected areas. It is concluded that more comprehensive management strategies are needed in order to effectively protect coral communities from degradation. Copyright © 2007 John Wiley & Sons, Ltd. [source] Feasibility of randomized controlled trials in liver surgery using surgery-related mortality or morbidity as endpoint,BRITISH JOURNAL OF SURGERY (NOW INCLUDES EUROPEAN JOURNAL OF SURGERY), Issue 9 2009M. A. J. van den Broek Background: There is a shortage of randomized controlled trials (RCTs) on which to base guidelines in liver surgery. The feasibility of conducting an adequately powered RCT in liver surgery using the dichotomous endpoints surgery-related mortality or morbidity was examined. Methods: Articles published between January 2002 and November 2007 with mortality or morbidity after liver surgery as primary endpoint were retrieved. Sample size calculations for a RCT aiming to show a relative reduction of these endpoints by 33, 50 or 66 per cent were performed. Results: The mean operative mortality rate was 1·0 per cent and the total morbidity rate 28·9 per cent; mean rates of bile leakage and postresectional liver failure were 4·4 and 2·6 per cent respectively. The smallest numbers of patients needed in each arm of a RCT aiming to show a 33 per cent relative reduction were 15 614 for operative mortality, 412 for total morbidity, 3446 for bile leakage and 5924 for postresectional liver failure. Conclusion: The feasibility of conducting an adequately powered RCT in liver surgery using outcomes such as mortality or specific complications seems low. Conclusions of underpowered RCTs should be interpreted with caution. A liver surgery-specific composite endpoint may be a useful and clinically relevant solution to pursue. Copyright © 2009 British Journal of Surgery Society Ltd. Published by John Wiley & Sons, Ltd. [source] Efficacy and safety of 800 and 1200 mg eslicarbazepine acetate as adjunctive treatment in adults with refractory partial-onset seizuresACTA NEUROLOGICA SCANDINAVICA, Issue 5 2009A. Gil-Nagel Objectives ,,, To evaluate the efficacy and safety of eslicarbazepine acetate (ESL) as adjunctive therapy in adults with partial-onset seizures. Material and methods ,,, Double-blind, placebo-controlled, parallel-group, multicenter study consisting of an 8-week baseline period, after which patients were randomized to placebo (n = 87) or once-daily ESL 800 mg (n = 85) or 1200 mg (n = 80). Patients received half dose during 2 weeks preceding a 12-week maintenance period. Results ,,, Seizure frequency over the maintenance period was significantly (P < 0.05) lower than placebo in both ESL groups. Responder rate was 23% (placebo), 35% (800 mg), and 38% (1200 mg). Median relative reduction in seizure frequency was 17% (placebo), 38% (800 mg), and 42% (1200 mg). The most common adverse events (AEs) (>10%) were dizziness, somnolence, headache, and nausea. The majority of AEs were of mild or moderate severity. Conclusions ,,, Once-daily treatment with ESL 800 and 1200 mg was effective and generally well tolerated. [source] Multicenter, Prospective, Randomized Safety and Efficacy Study of a New Atrial-Based Managed Ventricular Pacing Mode (MVP) in Dual Chamber ICDsJOURNAL OF CARDIOVASCULAR ELECTROPHYSIOLOGY, Issue 8 2005MICHAEL O. SWEENEY M.D. Background: Ventricular desynchronization caused by right ventricular pacing may impair ventricular function and increase risk of heart failure (CHF), atrial fibrillation (AF), and death. Conventional DDD/R mode often results in high cumulative percentage ventricular pacing (Cum%VP). We hypothesized that a new managed ventricular pacing mode (MVP) would safely provide AAI/R pacing with ventricular monitoring and DDD/R during AV block (AVB) and reduce Cum%VP compared to DDD/R. Methods: MVP RAMware was downloaded in 181 patients with Marquis DR ICDs. Patients were initially randomized to either MVP or DDD/R for 1 month, then crossed over to the opposite mode for 1 month. ICD diagnostics were analyzed for cumulative percentage atrial pacing (Cum%AP), Cum%VP, and duration of DDD/R pacing for spontaneous AVB. Results: Baseline characteristics included age 66 ± 12 years, EF 36 ± 14%, and NYHA Class II,III 36%. Baseline PR interval was 190 ± 53 msec and programmed AV intervals (DDD/R) were 216 ± 50 (paced)/189 ± 53 (sensed) msec. Mean Cum%VP was significantly lower in MVP versus DDD/R (4.1 ± 16.3 vs 73.8 ± 32.5, P < 0.0001). The median absolute and relative reductions in Cum%VP during MVP were 85.0 and 99.9, respectively. Mean Cum%AP was not different between MVP versus DDD/R (48.7 ± 38.5 vs 47.3 ± 38.4, P = 0.83). During MVP overall time spent in AAI/R was 89.6% (intrinsic conduction), DDD/R 6.7% (intermittent AVB), and DDI/R 3.7% (AF). No adverse events were attributed to MVP. Conclusions: MVP safely achieves functional atrial pacing by limiting ventricular pacing to periods of intermittent AVB and AF in ICD patients, significantly reducing Cum%VP compared to DDD/R. MVP is a universal pacing mode that adapts to AVB and AF, providing both atrial pacing and ventricular pacing support when needed. [source] CD4+ T cells mediate mucosal and systemic immune responses to experimental hookworm infectionPARASITE IMMUNOLOGY, Issue 6 2010B. DONDJI Summary Hookworm infection is associated with anaemia and malnutrition in many resource-limited countries. Ancylostoma hookworms have previously been shown to modulate host cellular immune responses through multiple mechanisms, including reduced mitogen-mediated lymphocyte proliferation, impaired antigen presentation/processing, and relative reductions in CD4+ T cells in the spleen and mesenteric lymph nodes. Syrian hamsters were depleted of CD4+ for up to 9 days following intraperitoneal injection (200 ,g) of a murine anti-mouse CD4 monoclonal IgG (clone GK1·5). CD4+ T-cell-depleted hamsters infected with the hookworm Ancylostoma ceylanicum exhibited a threefold higher mean intestinal worm burden and more severe anaemia than animals that received isotype control IgG. In addition, depletion of CD4+ T cells was associated with impaired cellular and humoral (serum and mucosal) immune responses to hookworm antigens. These data demonstrate an effector role for CD4+ T cells in hookworm immunity and disease pathogenesis. Ultimately, these studies may yield important insights into the relationship between intestinal nematode infections and diseases that are associated with CD4+ T-cell depletion, including HIV. [source] Efficacy of Aerobic Exercise on Coronary Heart Disease Risk FactorsPREVENTIVE CARDIOLOGY, Issue 2 2008George A. Kelley DA The authors examined the effects of aerobic exercise on selected coronary heart disease (CHD) risk factors using data from previously published meta-analyses. Using a random effects model, the effects of aerobic exercise on glycosylated hemoglobin (HbA1c) (mean, 95% confidence interval, ,0.9%, ,1.9% to 0.03%), resting systolic blood pressure (,6.9 mm Hg, ,9.1 to ,4.6 mm Hg), low-density lipoprotein cholesterol (,3.1 mg/dL, ,6.1 to 0 mg/dL), and body mass index (,1.3 kg/m2, ,2.5 to ,0.1 kg/m2) were either statistically significant or demonstrated a trend for statistical significance. Changes were equivalent to relative reductions of ,8.5%, ,4.7%, ,2.0%, and ,4.5%, respectively. Changes corresponded to estimated 5-year reductions in CHD mortality of 14%, 17%, 1.5%, and 5%, respectively. The results of this review reinforce the idea that aerobic exercise is an important nonpharmacologic intervention for improving selected CHD risk factors. [source] | |||||||||||||||||||||||||